Range-finder



f... H. HAMMOND, JR.

RANGE FINDER. I APPLICATION FILED IULY 27,1917 RENEWED DEC. 20. 1920.

Patented Nov. 29, 192 1.

2 SHEETS--SHEET INI/ENTOR HIS mole/75 J. H. HAMMOND, JR.

. RANGE FINDER.

APPLICATION FILED JULY 27,1917 RENEWED DEC. 20. 1920.

1,398,509,; Patented Nov. 29,1921.

2 SHEETSSHEET 2.

IYIIII/IIIIIIIIIII/I V/IIIIIIIIIlI/II IA"" WITNESS: 156 INVENTOH I I I 152 151 157 15:; 125 H/s ATTORNEY UNITED STATES PATENT OFFICE.

RANGE-FINDER.

Specification of Letters Patent.

Patented Nov. 29, 1921.

Application filed July 27, 1917, Serial 110/183,118. Renewed December 20, 1920. Serial No 432,138.

To aZZwh-om itmay concern:

Be it known that I, JOHN HAYS HAM- MOND, Jr., a citizen of the United States, and a resident of Gloucester, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Range-Finders, of which the following is a specification.

One of the objects of this invention is to provide an improved range finger particu larly adapted to determine the range of a target from a. gun, and also to determine the distances from the gun at which a plurality of shrapnel shells are successively exploded when thrown from the gun towardthe'target. In firing shrapnel shells at a target, the time fuse of each shrapnel shell is set or adjusted so as to cause each shell to be exploded at a point as near as possible to the target. The first shell thrown at the target from the gun may explode either some distance beyond the target or short of the target, and before firing the next shell the elevation of the gun is accordingly changed. 1f necessary, and the time fuse of the shell about to be fired is also adjusted, if necessary, to cause the shell to explode at a point as near the target as possible, the adjustment of the time fuse of the second shell being determined approximately as a result of the observation "of the explosion of the first shell. By providing means for. conveniently determining the distance from the gun at which the shells explode, this invention makes it possible for the gunner, after firing two shells which explode at different distances from the target, to adjust the time fuse of a third shell and succeeding shells quickly and with a high degree of accuracy.

In the accompanying drawings, Figure 1 is a diagrammatic top plan view of a range finder constructed in accordance with this invention; Fig. 2 is an enlarged sectional view of a detail of the same, on the line 22 of Fig, 1; Fig. 3 is a sectional View on the line 3-3 of Fig. 4; Fig. 4 is an enlarged sectional view on the line .44 of Fig. 1; Figs. 5 and 6 are a front and a side elevation respectively of a detail of the same.

Referring to the drawings, one embodiment of this invention comprises a range finderincluding a main sighting unit 10, a'secondary sighting unit 11, a pair of auxiliary sighting units 12 and 13', a main indicating unit 14 controlled by the main sighting unit 10, and a secondary indicating unit 15 controlled by the secondary sighting unitll and the auxiliary sighting units 12 and 13.

Each of the sighting units 10,11, 12 and 13 may be of any well known or suitable con- StI'UCtIQII, but in the form shown, the sighting units 10, 11, 12 and 13 are identical in construction, and each sighting unit comprises a substantially flat base-plate 25 which is arranged when in operation in a substantially horizontal plane, and is adj ustably and r gidly supported upon any suitable mountlng, for instance, upon the upper ends of four vertical adjusting screws 26, the lower ends of which are threaded into any suitable rigid sub-base 27. Each base-plate 25 is flexibly connected to the corresponding sub-base 27 by a universal joint 28, and each base-plate 25 is normally held in a fixed substantially horizontal position by the correspondlng adjusting screws 26 acting in opposition to the universal joint 28. V

Extending upwardly from each base-plate 25 and rigid therewith are two supports 29 and between the upper ends of each pair of supports 1s arranged a rigid frame30 which is arranged to rotate about a fixed horizontal axis on a pair of horoz ontally alined oppositely disposed trunnions 31 rigid with the frame 30 and rotatably supported in bearings provided therefor in the upper ends of the supports 29. For rotating each frame 30 about its horizontal axis, each frame is provided with a worm-gear 32 which is rigidly secured to the outer one of one of the trunnions 31 which is extended for this purpose, and engaging each worm-gear 31 is a worm 33 which is rigidly secured to a spindle 34 provided with a crank arm 35 and arranged to rotate about a fixed axis in the outer ends of a'pair of lugs 36 projecting from and rigid with the corresponding supports 29. Each frame 30 carries a shaft 38 which projects upwardly and which is held against longitudinal movement and is arranged to rotate with respect to its frame 30 about an axis coincident with its longitudinal axis and fixed with respect to the frame 30 and arranged to intersect the horizontal axis of rotation of the frame 30 on its trunnion-s 31. Rigidly secured to the upper end of each shaft 38 is a sleeve 39 in which is rigidly For transmitting the angular movement of each telescope about its movable axis, a gear is arranged within each frame 30 and surrounds and is rigidly secured to the corresponding shaft 38. Each gear 45 engages and actuates a pinion 46 which is rigldly secured to a spindle 47 held against longitudinal movement and arranged to rotate about an axis fixed with respect to the frame 30 to actuate electrical transmission mechanism 50 carried by the frame 30 and of any well known or suitable construction.

The main indicating unit 14 comprlses a normally stationary base-plate whlch carries a vertical spindle 61 projecting upwardly therefrom and rotatable with respect'thereto about a vertical axis coincident with its longitudinal axis. Rigidly secured to the upper end of the spindle 61 and projectin horizontally therefrom, is an arm 62 whlch is provided along its upper surface with suitable transversely extending graduations 63. Agear 65 surrounds and is rigidly secured to the spindle 61, and is enaged by a inion 66 which is arranged to. be rotated a out a fixed axis by means of any well known or suitable electrical motion repeating mechanism 68. The repeating mechanism 68 is electrically connected to the motion transmitting mechanism 50 of the main sighting unit 10 in a well known manner, by means of a four-wire cable 70,

, which includes a return wire 71 which is arranged to be energized by a battery 72 or other source of electric energy.

The secondary indicating unit 15 comprises a stationary base-plate which carries a vertical spindle 81 projecting upwardlly therefrom, and which 1s arranged to rotate about a vertical axis coincident with its longitudinal axis. A horizontal arm 82 is rigidly secured 'to the upper end of the spindle 81, and is arranged to cooperate with the graduated arm 62 of the main indicating unit '14. A gear 85 surrounds and is rigidly secured to the lower portion of the spindle 81, and is engaged by a pinion 86 which is arranged to be rotated about a fixed axis by any well known or. suitable electrical repeating mechanism 88. The repeating mechanism 88 is electrically connected to the main transmitting 50 of the secondary sighting unit 11 in a well known manner by means of a four-wire cable 90, including a return wire 91, which is arranged to be energized by a battery 92 or other source of electric energy.

snugly surrounding the vertical spindle 81 'of the secondary indicating unit 15, is a sleeve 95 which is rotatable with respect to the spindle 81, and which rests slidably at its lower end upon the gear 85. Rigidly se cured to the upper end of this sleeve 95 is a horizontal arm 96, which is arranged to cooperate with the'arm 62 of the main indicnism 115.

eating unit. Surrounding the lower portion of the sleeve 95 and rigidly secured thereto isa gear 97 which is engaged by a pinion 98 which is arranged to be rotated about a. Y

fixed vertical axis by any suitable electrical repeating mechanism 100. The repeating mechanism 100 is electrically connected to the transmission mechanism 50 of the inner auxiliary sighting unit 12 in a well known .manner, by means of a four-wire electric able with respect thereto is a sleeve 110, thethe upper end of this latter or outer sleeve correspondin gear 97 Rigidly secured to the upper en of this latter or outer sleeve is a horizontal arm 111 which is arranged to coiiperate with the arm 62 of the main indicating unit. Surrounding and rigidly secured to the lower portion of this outer sleeve 110 is a gear 112.which is engaged-by a pinion 113 which is arranged to be rotated about a fixed'vertical axis by means of electric motion repeating mecha- This repeating mechanism 115 is connected to the motion transmitting mechanism 50 of the outer auxiliary sighting unit 13 in a well known manner by means of a four-wire cable which includes a return wire 121 which is arranged to be energized by a battery 122. l

The base-plate 60 of the main indicating unit 14 may be arranged to slide toward and away from the secondary indicating unit 15 upon a rigid platform 125 and may be held securely in any desired position of adjustment in any suitable manner. In the form of the invention shown in the drawings the platform 125 is provided with an elongated slot extending radially with respect to the axis of the shaft 81 of the secondary indicating unit 15, and the plate 60 is provided with a rib 131 upon its under side and integral therewith and engaging slidably in the slot 130. The walls of the slot 130 are provided with marginal undercut recesses 132 and- 133' extending longitudinally of the slot, and a bolt 135 extends loosely through an aperture 136 provided therefor with a square head 137 which engages slidably and is held against rotation in the undercut recesses 132 and 133. The bolt 135 is provided with a thumb nut 140 which is threaded over the upper end of In the operation of this improved range finder, the main sighting units 10 and 11 are arranged so that their telescopes 40 will be spaced apart a suitable distance, and so that their fixed axes of oscillation will lie in the same straight horizontal line. The distance between the axes of the vertical spindles 61 and 81 of the main and secondary indicating units 1 1 and 15 is then adjusted accordingly by sliding the main indicating unit toward or away from the secfinder is to cotiperate.

andary indicating unit 15 as may be necessary. The two auxiliary sighting units 12 and 13 are arranged as near to the secondary sighting unit 11 as ma be practicable and still permit the operation of the telesco es 40 of the auxiliary sighting units. Pre erably the auxiliary sighting units 12 and 13 vare also so arranged that the horizontal fixed axes of rotation of their telescopes 40 will lie substantially in the same line which includes the horizontal axes of rotation of the telescopes 40 of the main and secondary sighting units '10 and 11. The main sighting unit 10 is also located as near as is practicable to the gun 150 with which the range The plate carrying the main and secondary indicating units 14 and 15 may be arranged in any convenient position for observation by the one who is to aim the gun 150, or isto transmit instructions to the gunner.

In firing shrapnel from the gun 150 at a target 155, the telescopes 40 of the main and secondary sighting units 10 and 11 are simultaneously sighted upon the target 155 and the rotary motions of' these telescopes are transmitted by the corresponding transmitters to the corresponding repeaters 68 and 88 of the main indicating unit 14 and the secondary indicating unit 15 respectively. The repeater 68 of themain indicating unit rotates the corresponding arm 62 through an angle equal to the angle of rotation of the telescope. 410 of the main sighting unit 10, and the repeater 88 of the secondary indicating unit rotates the arm 82 of the secondary indicating unit through an angle equal to the angle of rotation of the telescope 40 of the secondary sighting unit. The point on the scale of the arm 62 where the arm 62 is crossed by the arm 82 now indicates the distance of the target 155 if from the telescope 10 of themain sighting unit.10, and consequently the approximate distance of the target 155 from the gun 150.

- The gun 150 is then elevated in accordance with the range of the target thus found and is sighted upon the target. A shrapnel shell having its fuse adjusted as nearly as possible in accordance with the indicated range is then fired from the gun 150, and as soon as possible after the shell explodes, which may be at a point 156 beyond the target, the telescope 40 of the corresponding outer auxiliary sighting unit 13 is directed upon the point of explosion 156 of the shell as indicated by the'puif of smoke. The angle of rotation of this auxiliary telescope 40 is transmitted by the corresponding transmitter50 to the corresponding repeater 115 of the secondary sighting unit and rotates the corresponding arm 111 through an equal angle. The point where this arm 111 crosses the arm 62 indicates approximately the range of the point 156 of explosion of the shell from the gun 150, and the distance between the two points where the two arms 82 and 111 cross the arm 62 indicates on the scale the distance between the point of explosion 156 and the target 155, and enables the gunner to adjust the fuse of a second shell with greater accuracy.

The second shell is then fired from the gun, and as soon as possible after it explodes, which may be at a point 157 short of the target 155, the telescope 40 of the corresponding inner auxiliary sighting unit 12 is directed upon the point of explosion 157 as indicated by the puff ofr'smoke. The angle of rotation of this latter telescope 40 is transmitted through the corresponding transmitter 51 and to the corresponding repeater 100 of the secondary indicating unit 15, and this repeater rotates the corresponding arm 96 through an equal angle. The point where the arm 96 crosses the arm 62 indicates the range of the point 157 of the second explosion from the gun 150, and the distance between the points where the two adjust the fuse of the third shell with Sue I acciiracy that in most cases when fired from the gun it will explode at a point approximatelyat or in'" front of the target 155.

This improved range finder has been designed to be used chiefly in connection with the firing of shrapnel shells at aircraft, and when so used the range and elevation of the aircraft from the gun is first found by a range finder of any suitable construction. After having thus found the range and elevation of the aircraft the gunner begins firing the shrapnel at the aircraft, and the range finding device forming the subject matter of the present application is then used as hereinbefore described, as an auxiliary system to determine 110w much the shots are flong or short of the aircraft so that the time-fuses of the shrapnel shells may be adjusted accurately.

Although only a single form has been shown in which this invention may be embodied, it is'to be understood that the invention is not limited to any specific construction or arrangement but might be embodied in -various forms without departing from the spirit-of the invention or the scope of the ap nded claims.

aving thus fully described my'in'vention,

.I claini and desireto protect by Letters Patent of the United States:

1. In a range finder, the combination with a main sighting unit, of a secondary sighting unit, an auxiliary sighting unit, a main indicating element controlled by said main sighting unit, and a plurality of separately movable secondary indicating'elements separately controlled by said seconda sighting unit and said auxiliary sighting unit respecv, tively, said secondary indicating elements being arranged to cooperate with said main indicating element to indicate a plurality of distances.

2. In a range finder, the combination with a main sighting el ent, of a secondary sighting element, a plurality of auxiliary rality of distances.

sighting elements, a main indicating element controlled by said main sighting element, a secondary indicating element controlled by said secondary sightin element, and a plurality of secondary in icating elements controlled by said auxilia sighting elements respectively, said secon ary indicating elements being arran ed to cooperate with said main indicating e e ment to indicate a-plu- 3. In a range finder, the combination with a main sighting element, of a plurality of auxiliary sighting elements, a main indicating element controlled by said main sighting element, and a pluralit of secondary indicating elements control ed b saidauxiliary sightlng elements respective y and arranged to cooperate with said main indicating element to indicate a plurality of distances.

4. 'The combination with a main sighting element arranged to rotate about a. given distances, and'electrical motion transmission means operatively connecting said secondary sighting elementand said auxiliary si hting element respectively with said secon ary indicating elements.

5. The combination with a main sighting element arranged to rotate about a given axis, of a secondary sighting element arranged to rotate about a given axis independently of said main sighting element, an auxiliary sighting element arranged to ro tate about a given axis independently of either of said first mentioned sighting elements, 9. main indicating element, electrical mot-ion transmission means operatively connecting said main sighting element with said main indicating element, a pair of separately movable secondary indicating elements arranged to coiiperate with said main indicating element to indicate a plurality of distances, and electrical motion transmissionv means operatively connecting said secondary sighting element and said auxiliary sighting element respectively with said secondary indicating elements, said axesof said sighting elements being separately movable and said motion transnussion means being arranged to transmit the angular movements'of said sighting elements about said1 axes to said indicating elements respective y.

6. In a range finder, the combination with a main sighting unit, of a secondary sighting unit, an auxiliary sighting unit, a main indicating element cont-rolled by said main sighting unit, and a plurality of separately movable secondary indicating elements separately controlled by said secondary sighting unit and said auxiliary sighting unit respectively, said secondary indicating elements being arran d to cooperate with said main indicating e ement to indicate a plurality of distances, and each of. said sighting units being arranged to be rotated about an axis arranged to be rotated in a fixed plane.

7. In a range finder, the combination with a main sighting element, of a secondary sighting element, a pluralit of auxiliary sighting elements, a main indlcating element controlled by said main sighting element, a secondary indicating element controlled by said secondary sightin element, and a plurality of secondary in icating elements controlled by said auxilia sighting elements respectively, said secon ary indicating elements being arran d to cooperate with said main indicating e ement to indicate a plurality of distances, and each of said sighting units being arranged to be rotated separately about an axis arranged to be moved in a fixed plane. v

8. In a range finder, the combination with a main sighting'element, of a secondary sighting-element, a plurality of auxiliary sighting elements, a main? indicating element controlled by said main sighting element, a secondary indicating element controlled by said secondary sighting element, and a plurality of secondary indicating elements controlled by saidauxiliary sighting elements respectively, said secondary indleating elements belng arranged to coiiperate' with said main indicating element to. indicate a plurality of distances, and each of said sighting units being arranged to be .ing unit, a plurality of auxiliary sighting umts, a main indicating element controlled by said main sighting 'unit, and a plurality of separately movable secondary indicating elements separately controlled by said secondary sighting unit and said auxiliary sighting unit respectively, said secondary indicating elements, being arranged tocooperate with said main indicating elements to indicate a plurality of distances, and each of said elements being arranged to be moved in a plane which rotates about a line joining said main and secondary sighting units.

10. In a range finder, the comblnation with a main sightin unit, of a secondary sighting unit, a plura ity of auxiliary sight mg units, a main indicating'element controlled by said main "sighting unit, and a plurality of separately movable secondary indicating elements separately controlled by said secondary sighting unit and said auxiliary sighting unit respectively, said secondary indicating elements being arranged to cooperate with said main indicating element to indicate a plurality of distances,

and each of said sighting units being arranged to be rotated about an axis arranged to move in a plane perpendicular to a line joining said main and secondary sighting units.

11. In a range finder, the combination with a plurality of sighting units, and a plurality of indlcating elements, one of said mdicating elements being. arranged to be controlled by one of said sighting units, and the remaining indicating elements being arranged to be controlled respectively by the remaining sighting units, and one of said indicating elements cooperating with the other indicating elements to indicate a plurality of distances.

12. In a range finder, the combination With a plurality of sighting-units, a plurality of indicating elements, means operated by one of said sighting units for controlling one of said indicating elements, and means operated by the remaining sighting units for respectively operating the remaining indicating elements, one of said indicating elements cooperating with the other indicating elements to indicate a plurality of distances.

Signed at New York, in the county of New York and State of New York, this 21st day of Jul A. D. 1917.

. JO N HAYS HAMMOND, JR. 

